Abdominal aortic aneurysms may be treated minimally-invasively by endovascular aneurysm repair, for example by placement of abdominal aortic aneurysm stentgrafts (in the following referred to as “stents”), which is placed by means of percutaneous catheterization. During placement of stents it is important that the ostias of the renal arteries are not blocked by a placed stent so that the blood flow to the kidneys is not obstructed. Stent placement may usually be accomplished by a minimal invasive treatment in the form of forwarding the stent within the artery to the desired location and expanding it there. It is widespread to monitor this procedure and guide the clinician for example by means of an X-ray image acquisition apparatus, where actual X-ray images obtained by the image acquisition device, for example of a C-arm type, are overlaid onto a previously obtained image with a contrast agent present in the respective vessels.
Unfortunately, the exact connection points of renal arteries to the aorta are not always visible in one view with a fixed viewing angle. This is particularly the case when the connection points are located at the back of the aorta when a standard anterior-posterior-projection is used. As a consequence, forwarding a stent to its desired location in an aorta may necessitate multiple manual changes of viewing directions of the respective examination apparatus in order to prevent the blocking of renal arteries.
WO 2008/047270 A1 shows a method for displaying images of an object under examination, wherein displayed three-dimensional images are combined with displays of two-dimensional images corresponding to a selected projection angle.